Janer G, LeBlanc G A, Porte C
Environmental Chemistry Department, IIQAB-CSIC-C/Jordi Girona 18, 08034 Barcelona, Spain.
Gen Comp Endocrinol. 2005 Sep 15;143(3):211-21. doi: 10.1016/j.ygcen.2005.03.016.
A comparative approach was taken in this study to evaluate androgen (androstenedione and testosterone) metabolism in three invertebrate species: the gastropod Marisa cornuarietis, the amphipod Hyalella azteca, and the echinoderm Paracentrotus lividus. The existence of 17beta/3beta-hydroxysteroid dehydrogenase (HSD) and 5alpha-reductase catalyzed reactions was demonstrated in all three species. Androstenedione was primarily converted to 5alpha-androstanedione in M. cornuarietis, while it was primarily metabolized to testosterone in P. lividus and H. azteca. In addition, and consistent with vertebrate findings, tissue specific pathways and sexual dimorphism in androgen metabolism were observed. Namely, testosterone was metabolized to dihydrotestosterone in P. lividus gonads (via 5alpha-reductase), and metabolized to 4-androstene-3beta,17beta-diol in the digestive tube (via 3beta-hydroxysteroid dehydrogenase). Furthermore, the synthesis of 17beta-reduced metabolites of androstenedione (testosterone and dihydrotestosterone) was 3- to 4-fold higher in males of M. cornuarietis than in females. Organotin compounds, which have been shown to interfere with some aspects of androgen metabolism, had no major effect on testosterone metabolism in any of the three species. Fenarimol enhanced 5alpha-reductase-mediated catalysis in gonads of P. lividus. Overall, results demonstrate the ubiquity of some androgen biotransformation processes in invertebrates and reveals interphyla differences in androgen metabolic pathways, and different sensitivity of these pathways to some xenobiotics.
本研究采用比较方法，评估三种无脊椎动物物种中的雄激素（雄烯二酮和睾酮）代谢：腹足纲的玛瑙螺（Marisa cornuarietis）、双甲纲的墨西哥高原钩虾（Hyalella azteca）和棘皮动物的紫球海胆（Paracentrotus lividus）。在所有这三个物种中均证实了17β/3β-羟基类固醇脱氢酶（HSD）和5α-还原酶催化反应的存在。在玛瑙螺中，雄烯二酮主要转化为5α-雄烷二酮，而在紫球海胆和墨西哥高原钩虾中，它主要代谢为睾酮。此外，与脊椎动物的研究结果一致，观察到雄激素代谢存在组织特异性途径和性别二态性。具体而言，在紫球海胆的性腺中，睾酮通过5α-还原酶代谢为二氢睾酮，而在消化管中通过3β-羟基类固醇脱氢酶代谢为4-雄烯-3β,17β-二醇。此外，玛瑙螺雄性中雄烯二酮的17β-还原代谢产物（睾酮和二氢睾酮）的合成比雌性高3至4倍。已证明会干扰雄激素代谢某些方面的有机锡化合物，对这三个物种中的任何一个物种的睾酮代谢均无重大影响。氯苯嘧啶醇增强了紫球海胆性腺中5α-还原酶介导的催化作用。总体而言，结果表明某些雄激素生物转化过程在无脊椎动物中普遍存在，并揭示了不同门之间雄激素代谢途径的差异，以及这些途径对某些外源化合物的不同敏感性。
